org-element-cache: org-set-tags (C-c C-q) makes Emacs unresponsive at times

[Kaushal Modi]

Hello Ihor,

> The issue here had nothing to do with hanging. You are probably seeing
> yet another bug.

ok.

> By hang, do you mean that even C-g does not restore responsiveness?

Typically, within a second of doing C-c C-q, I would know that the
buffer is going to freeze, and if I do C-g soon enough, Emacs would
recover in a second or two.

But if I wait 5-6 seconds and then do C-g, it could take minutes to
recover, and I often do pkill SIGUSR2 from the terminal to get back.

Sorry, but since then I set org-element-use-cache to nil once that
issue comes back. It's usually that I am between something and I don't
think of getting a backtrace on C-g (Now I have made a note to self to
provide a backtrace in this thread when that issue repeats).

---

Right now, I set org-element-use-cache back to t, did M-x
toggle-debug-on-quit and did a couple of C-c C-q in a 10k line Org
buffer .. this time, it's responsive and snappy :|

I'll keep you posted. Thanks!!

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Org mode version 9.5 (release_9.5-415-g9b58ea)
Emacs version: GNU Emacs 28.0.91 (build 5, x86_64-pc-linux-gnu, GTK+
Version 3.22.30, cairo version 1.15.12) of 2022-01-18, built using
commit f393d0d441c3746f98007ae54341870a296bf809.